U.S. patent application number 09/296462 was filed with the patent office on 2001-11-15 for image processing apparatus and method of controlling the same.
Invention is credited to AIKOH, YASUYUKI, CHISHIMA, HIDEAKI, ISEKI, YUKIMASA, MORITA, TETSUYA, SUGIURA, TAKASHI, UCHIZONO, TAKEHARU.
Application Number | 20010040703 09/296462 |
Document ID | / |
Family ID | 26384600 |
Filed Date | 2001-11-15 |
United States Patent
Application |
20010040703 |
Kind Code |
A1 |
ISEKI, YUKIMASA ; et
al. |
November 15, 2001 |
IMAGE PROCESSING APPARATUS AND METHOD OF CONTROLLING THE SAME
Abstract
An image processing apparatus is provided which comprises an
image reading section for reading an original document by causing
an image reading head of the image reading section to move relative
to an original document; an image recording section for recording
an image on a recording medium in accordance with an image signal;
a power source for supplying power to the image reading section and
the image recording section; and a control device for controlling
the speed of movement of the image reading head according to an
operating state of the image recording section. The image
processing apparatus of the invention overcomes problems associated
with the use of prior art image forming apparatus, such as
multi-function copying machines, that include an image reading
section and an image recording section, and which require the use
of large-capacity power sources for supporting the electrical loads
of various components that may be operating simultaneously within
the individual apparatuses.
Inventors: |
ISEKI, YUKIMASA; (ABIKO-SHI,
JP) ; SUGIURA, TAKASHI; (IBARAKI-KEN, JP) ;
AIKOH, YASUYUKI; (TORIDE-SHI, JP) ; MORITA,
TETSUYA; (YOKOHAMA-SHI, JP) ; UCHIZONO, TAKEHARU;
(ABIKO-SHI, JP) ; CHISHIMA, HIDEAKI; (HINO-SHI,
JP) |
Correspondence
Address: |
FITZPATRICK CELLA HARPER & SCINTO
30 ROCKEFELLER PLAZA
NEW YORK
NY
10112
US
|
Family ID: |
26384600 |
Appl. No.: |
09/296462 |
Filed: |
April 22, 1999 |
Current U.S.
Class: |
358/474 ;
358/496 |
Current CPC
Class: |
H04N 2201/04755
20130101; H04N 1/00885 20130101; H04N 1/1013 20130101; H04N 1/0473
20130101; H04N 1/193 20130101 |
Class at
Publication: |
358/474 ;
358/496 |
International
Class: |
H04N 001/04 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 23, 1998 |
JP |
113257/1998 |
Feb 23, 1999 |
JP |
044653/1999 |
Claims
What is claimed is:
1. A image processing apparatus, comprising: an image reading
section having an image reading head, said image reading section
for reading an original document by causing the image reading head
to move relative to said original document; an image recording
section for recording an image on a recording medium in accordance
with an image signal; a power source for supplying power to said
image reading section and said image recording section; and control
means for controlling the speed of movement of said image reading
head within said image reading section according to an operating
state of said image recording section.
2. An image processing apparatus according to claim 1, further
comprising determination means for determining whether or not said
image recording section is being started.
3. An image processing apparatus according to claim 2, wherein
during a first period, said image reading head moves while reading
said original document, and during a second period, said image
reading head returns to an original position, and wherein said
control means controls the speed of movement of said image reading
head during said second period.
4. An image processing apparatus according to claim 3, wherein when
it is determined by said determination means that said image
recording section is being started, said control means sets the
speed of movement of said image reading head to a speed slower than
a normal speed.
5. An image processing apparatus according to claim 2, wherein said
image recording section comprises rotation driving means and a
polygon mirror which scans a light beam, said rotation driving
means for drivingly rotating said polygon mirror, and said control
means sets the speed of movement of said image reading head to a
speed slower than a normal speed when said rotation driving means
is being started.
6. An image processing apparatus according to claim 2, wherein said
image recording section comprises fixing means for fixing a toner
image on the recording medium, and said control means sets the
speed of movement of said image reading head to a speed slower than
a normal speed when said fixing means is being started.
7. A method for controlling an image processing apparatus,
comprising steps of: reading, with an image reading section, an
original document by causing an image reading head of the image
reading section to move relative to said original document;
recording, with an image recording section, an image on a recording
medium in accordance with an image signal; supplying power from a
power source to said image reading section and said image recording
section; and controlling the speed of movement of said image
reading head within said image reading section according to an
operating state of said image recording section.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an image processing
apparatus, such as a copying machine.
[0003] 2. Description of the Related Art
[0004] Hitherto, multi-function copying machines have been
commercially available. Multi-function copying machines typically
comprise an image reading section, an image forming section, a
facsimile communication section, and a PDL (page description
language) receiving section, thereby realizing, for example, a
copying function, a facsimile function, a printer function, a
scanner function, and the like in one machine. In such copying
machines, these functions can be performed simultaneously. For
example, while the image forming section is being used for a
printer function, the image reading section can be used to perform
facsimile transmission.
[0005] However, such apparatuses typically include various
electrical loads, such as a polygon motor for rotating a polygon
mirror which scans laser light, a main motor for rotating a rotary
drum, a heat roller of a fixing means, and the like, and thus
require a large current at the start-up thereof. In particular, in
multi-function copying machines, since a section inside the
apparatus may be operating while one or more of these loads are
being started, a large-capacity power source is required.
SUMMARY OF THE INVENTION
[0006] Accordingly, it is an object of the present invention, the
achievement of which solves the above-described problems, to
provide an image processing apparatus and a method of controlling
the same.
[0007] According to one aspect of the present invention, this
objective is achieved by providing an image processing apparatus,
comprising: an image reading section for reading an original
document by causing an image reading head of the image reading
section to move relative to the original document; an image
recording section for recording an image on a recording medium in
accordance with an image signal; and a power source for supplying
power to the image reading section and the image recording section,
wherein there is further provided a control means for controlling
the speed of movement of the image reading head within the image
reading section according to an operating state of the image
recording section.
[0008] According to another aspect of the present invention, the
object of the invention is achieved by providing a method for
controlling an image processing apparatus, comprising steps of:
reading, with an image reading section, an original document by
causing an image reading head of the image reading section to move
relative to the original document; recording, with an image
recording section, an image on a recording medium in accordance
with an image signal; and supplying power from a power source to
the image reading section and the image recording section, the
method further comprising the step of controlling the speed of the
image reading head within the image reading section according to an
operating state of the image recording section.
[0009] The above-described and further objects, aspects and novel
features of the invention will become more apparent from the
following detailed description when read in connection with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 shows control blocks of a polygon motor and a scanner
motor according to a first embodiment of the present invention.
[0011] FIG. 2 is an illustration of an image forming apparatus
according to the first embodiment of the present invention.
[0012] FIGS. 3a-3c show timing chars representing a start-up
operation of the polygon motor.
[0013] FIGS. 4a-4d show timing charts 1 of scanner motor control,
during a time period other than that when the polygon motor is
being started.
[0014] FIGS. 5a-5d show timing charts 2 of scanner motor control
during a time period when the polygon motor is being started.
[0015] FIG. 6 is a basic diagram of an image reading apparatus
according to a second embodiment of the present invention.
[0016] FIG. 7 is a basic diagram of a copying system according to
the second embodiment of the present invention.
[0017] FIG. 8 shows relationships between current consumed by a
load and power consumption.
[0018] FIG. 9 is a diagram showing features of the second
embodiment of the present invention.
[0019] FIG. 10 shows details of a motor control driver 623 of FIG.
9.
[0020] FIG. 11 is a flowchart of processing according to the second
embodiment of the present invention.
[0021] FIGS. 12a-12c show timing charts of power consumption
according to the second embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] A multi-function copying machine according to the present
invention will now be described below with reference to the
accompanying drawings.
First Embodiment
[0023] FIG. 2 shows a multi-function copying machine according to a
first embodiment of the present invention.
[0024] The multi-function copying machine of this embodiment
generally comprises an image reading section 1 for reading an
original document image and converting it into image signals, and
an image recording section 2 for recording an image on transfer
paper on the basis of the image signals.
[0025] The construction of the image reading section 1 is described
first. Referring to FIG. 2, an exposure lamp 201, formed from a
fluorescent lamp, a halogen lamp, or the like, irradiates an
original document on a document placement glass (document holder)
200 while moving in a direction perpendicular to its length
direction. The reflected light from the original document as a
result of the radiation by the exposure lamp 201 is reflected by
first, second, and third mirrors 202, 204, and 205, respectively,
and enters a lens 207. Here, with respect to the movement of a
first movable member 203 composed of the exposure lamp 201 and the
first mirror 202, a second movable member 206 composed of the
second mirror 204 and the third mirror 205 moves at half speed,
causing the distance from the radiated surface of the original
document to the lens 207 to be maintained constant. The first
movable member 203 and the second movable member 206 constitute an
image reading head, that is, a scanner head, which will be
described below, and these components are driven by a scanner motor
152, which will also be described below.
[0026] With this construction, while the reflected light from the
original document is formed into an image on the light-receiving
section of a CCD line sensor 208, in which an array of several
thousand photoreceptor elements are arranged in lines via the
mirrors 202, 204, and 205, and the lens 207, and is
photo-electrically converted sequentially in units of lines by the
CCD line sensor 208, the scanner head moves in a direction to the
right in the figure. This makes it possible to scan the entire
surface of the original document. When the scanning of the entire
surface of the original document is completed, the scanner head
moves in a direction to the left in the figure and stops where it
returns to its original position. The foregoing is a description of
the image recording section.
[0027] An electrical signal (in the form of photo-electrically
converted image information) obtained in this manner is then
processed by a signal processing section (not shown), after which
it is pulse-width-modulated, causing a laser to be driven.
[0028] Next, the construction of the image recording section 2 is
described.
[0029] An exposure control section 210 drives a semiconductor laser
in accordance with a PWM-modulated image signal, which is output
from the signal processing section, in order to radiate a light
beam onto the surface of a photosensitive member 240. A polygon
mirror 143 is used to deflect and scan a light beam in a direction
parallel to the axial direction of the drum-shaped photosensitive
member 240, and the photosensitive member 240 is rotated at a
constant speed, making it possible for the light beam to scan on
the photosensitive member 240 in a two-dimensional manner. This
polygon mirror 143 is drivingly rotated by a polygon motor 142,
which will be described below. The exposure control section 210 is
cooled by a cooling fan 209.
[0030] Meanwhile, in the photosensitive member 240, before the
light beam is received, electrical charge remaining on the
photosensitive member 240 is removed by a pre-exposure lamp (not
shown), and the surface thereof is uniformly charged by a primary
charger 228. Then, as a result of receiving a light beam from the
semiconductor laser driver by the exposure control section 210, as
described above, an electrostatic latent image is formed. Next, the
electrostatic latent image on the surface of the drum is made
visible using a developing agent (toner) by a developing unit 211.
The toner image which is made visible is then transferred to
transfer paper fed from a paper-feed cassette 223 or 224 in a
transfer section 239. Then, the transfer paper is passed through a
transfer roller 213 (which has a heater contained therein) that is
heated to a predetermined target temperature, and, as a result, the
toner image on the transfer paper becomes fixed onto the transfer
paper. The transfer paper with the fixed toner image is then
ejected in a paper-ejection section 242. The photosensitive member
240 is rotated by a main motor (not shown).
[0031] Although not shown, there is a case in which an automatic
document feeder (ADF) is disposed on the document holder glass 200.
This is such that when a plurality of documents sheets are set in a
document placement section of the ADF, documents are fed one by one
onto the document holder glass 200 in accordance with a signal from
a CPU of the main unit of this multi-function copying machine.
[0032] Not only are the image signals obtained by the image reading
section sent to the image recording section in order to obtain a
copy image, but also these image signals can be transmitted by a
facsimile via a facsimile communication section (not shown) and a
public network, and/or can be sent to a host computer over a
network. Furthermore, the image recording section not only records
an image in accordance with an image signal sent from the image
reading section, but can also record an image in accordance with an
image signal received in a facsimile communication via a public
network and a facsimile communication section (not shown), and/or
an image signal sent from a host computer via a network and a PDL
receiving section (not shown). Therefore, the image reading section
and the image recording section are not necessarily started and
used at the same time, and one of them may be started and used at a
necessary timing as required.
[0033] Next, the control of the polygon motor 142 and the scanner
motor 152 is described. FIG. 1 shows control blocks representing
these motors.
[0034] Referring to FIG. 1, reference numeral 142 denotes the
above-mentioned polygon motor for rotating the polygon mirror 143.
Reference numeral 141 denotes a polygon-motor driving circuit for
driving the polygon motor 142. Reference numeral 152 denotes the
above-mentioned scanner motor for reciprocating the scanner head.
Reference numeral 151 denotes a scanner-motor driving circuit for
driving the scanner motor 152. Reference numeral 101 denotes a
controlling CPU for outputting various control signals to the
polygon-motor driving circuit 141 and the scanner-motor driving
circuit 151. Reference numeral 161 denotes a power source for
supplying power to the polygon-motor driving circuit 141 and the
other sections within the image recording section, and to the
scanner-motor driving circuit 151 and the other sections within the
image reading section.
[0035] Examples of cases in which the image recording section is
started up while the image reading section is not operating include
facsimile receptions from a public network, and PDL receptions from
a host computer. Furthermore, in such cases, examples of cases in
which the image reading section is started up include facsimile
transmissions to the public network and transmissions of image
signals to the host computer.
[0036] With reference to the timing charts of FIGS. 3a-3c, the
operation when the polygon motor 141 is started up is described.
First, in an initial state, both a rotation signal 121 and a
steady-state rotation signal 122 are at an H level (t<t1). Then,
when an instruction of image formation is made from the main
control section (not shown), the controlling CPU 101 changes the
level of the rotation signal 121 from H to L (t=t1), and the
polygon motor 142 begins to rotate gradually. The driving current
during the time when this polygon motor 142 is being started is
larger than the driving current during the steady-state rotation
state.
[0037] Subsequently, when the polygon motor 142 reaches a
steady-state rotation state (t=t2), the polygon-motor driving
circuit 141 reduces the level of the steady-state rotation signal
122 to L, thereby notifying the controlling CPU 101 of the fact
that the polygon motor 142 has entered a steady-state rotation
state. Therefore, in this embodiment, the control conditions for
the scanner head are changed during a period in which the polygon
motor 142 is being started.
[0038] The control of the scanner motor 152 will now be described.
When the scanner motor 152 rotates in a forward direction, the
scanner head comprising the first movable member 203 and the second
movable member 206 moves in a direction to the right in FIG. 2.
When the scanner motor 111 rotates in a reverse direction, the
scanner head moves in a direction to the left in FIG. 2. The
scanner motor 152 used in this embodiment is preferably a pulse
motor, which is rotated at a number of revolutions corresponding to
the frequency of a given pulse signal, and which requires a level
of driving current corresponding to a required torque.
[0039] Initially, when reading of an image is instructed from the
main control section (not shown), the controlling CPU 101
determines whether or not the polygon motor 142 is being started
according to the rotation signal 121 and the steady-state rotation
signal 122. That is, as is also clear from FIGS. 3a-3c, it is
determined that when the rotation signal 121 is at an L level and
the steady-state rotation signal 122 is at an H level, the polygon
motor 142 is being started.
[0040] Next, referring to the timing charts of FIGS. 4a-4d, a
description is given of the control operation of the scanner motor
152 during a time when the polygon motor 142 is in a steady-state
rotation state or in a non-operating state, that is, during a time
when the polygon motor 142 is not being started. In FIGS. 4a-4d, it
is assumed that, when a rotation signal 131 is at an H level, the
scanner motor 152 is not operating, and that, when the rotation
signal 131 is at an L level, the scanner motor 152 is being
rotated. A forward/backward signal 132 is used to indicate the
direction of rotation of the scanner motor 152. When the
forward/backward signal 132 is at an H level, the scanner head is
moved in a forward direction, and when it is at an L level, the
scanner head is moved in a reverse direction. A target number of
revolutions signal 133 is used to indicate the number of
revolutions of the scanner motor 152. By providing active pulses of
a desired frequency, it is possible to cause the scanner motor 152
to be rotated at a number of revolutions that is proportional to
the frequency of these pulses. Reference numeral 134 denotes a
constant-current-value switch signal, which is used to indicate a
constant-current value Is employed when the scanner motor 152 is
driven with a constant current. When the constant-current-value
switch signal is at an H level, the scanner motor 152 is driven
with a constant current represented by value Is=I.alpha., and, when
it is at an L level, the scanner motor 152 is driven with constant
current represented by value Is=I.beta. (I.beta.>I.alpha.).
[0041] In an initial state, the rotation signal 131, the
forward/backward signal 132, and the constant-current-value switch
signal 134, are at an H level, and the target number of revolutions
signal 133 is at an L level. Here, when the controlling CPU 101
changes the level of the rotation signal 131 from H to L, and
active pulses of a frequency f.alpha. are provided as the target
number of revolutions signal 133, the scanner motor 152 rotates in
a forward direction by a number of revolutions that is proportional
to this pulse frequency f.alpha., and the scanner head begins to
move forward (t=ta). The driving current Is at this time is set to
value I.alpha.. Then, when reading of the entire surface of the
original document by the scanner head is completed, the controlling
CPU 101 changes the level of the forward/backward signal 132 to L
(t=tb), causing the scanner head to move backward. In this case,
pulses of a higher frequency f.beta. are provided as the target
number of revolutions signal 133, causing the scanner head to move
backward at a high speed. Since a large torque is required for
high-speed rotation, the constant-current-value switch signal 134
is changed to level L, and the constant-current value is set to
I.beta.. Then, when the scanner head returns to its original
position, the signal parameters are returned to their initial
values (t=tc).
[0042] Next, referring to the timing charts of FIGS. 5a-5d, a
description is given of the control operation of the scanner motor
152 in a case in which the polygon motor 142 is being started. From
an initial state (t<ta) up to a time when the reading of the
original document by the scanner head is completed, the various
signals are similar to those described above. Then, at a time t=tb,
the controlling CPU 101 changes the level of the forward/backward
signal 132 to L (t=tb), causing the scanner head to move backward.
In this case, however, by providing pulses of a frequency f.gamma.
lower than the above-mentioned frequency f.beta.
(f.gamma.<f.beta.), as the target number of revolutions signal
133, the scanner head is moved backward at a speed lower than that
described above. Since a torque larger than that of the
above-described case is not required, the constant-current-value
switch signal 134 is kept at an H level, and the constant-current
value is maintained at a lower value I.alpha.. The value of the
driving current Is at this time is denoted as I.gamma.. When the
scanner head returns to its original position, the signal
parameters are returned to their initial values, terminating the
processing.
[0043] More specifically, when the scanner head is moved backward
in the normal case, the frequency of the target number of
revolutions signal 133 may be originally set at f.beta.=4f.alpha.
so that, when the polygon motor 142 is being started, the frequency
is lowered to approximately f.gamma.=2f.alpha.. As a result, the
backward speed of the scanner head, when the polygon motor 142 is
being started, becomes one-half of that in the normal case.
[0044] As a result of the above-described control operation, while
the polygon motor 142 is being started, a necessary torque is
decreased by making the backward speed of the scanner head slower
than usual, and the driving current of the scanner motor 152 is
lowered, thereby making it possible to employ a power source 161
with a reduced capacity relative to that of power sources used in
prior art copying systems.
[0045] The foregoing description described a case in which the
backward speed of the scanner head is controlled according to
whether or not the polygon motor 142 within the image recording
section is being started. Similar advantages can also be obtained
by controlling the backward speed of the scanner head as described
above, according to operating states of loads, other than the
polygon motor 142, within the image recording section. An example
of a load other than the polygon motor 142 includes a main motor
for rotating the photosensitive member 240 in FIG. 1.
Second Embodiment
[0046] In a second embodiment of the present invention, the return
of a portion of the image reading section along the subscanning
direction (hereinafter referred to as "backscan") is decelerated
only during the period from when the power to the image recording
section is switched on until the image recording section becomes
operable. This makes it possible to decrease the driving current
consumed in the backscan. Since the current--power consumption
characteristics of the load are as shown in FIG. 8, as a result of
a reduction in the current, the power consumption is reduced. By
distributing the amount corresponding to the power consumption to
the heat-source supply current of the heat roller 213, electricity
is consumed economically.
[0047] FIG. 6 is a diagram of an image reading apparatus (also
referred to as an "image reading section") 614 in this copying
system (image processing apparatus). The image reading apparatus
614 optically and electrically reads an image of an original
document placed on a document holder (platen glass) 601. In
addition to a cover 603 of the document holder, this image reading
apparatus 614 comprises a document radiation lamp 604, scanning
mirrors 605, 606 and 606', an image-forming lens 607, and a CCD
image sensor 608. The document radiation lamp 604, which is
preferably formed of a halogen lamp, is integrated with the
scanning mirrors 605, 606 and 606' and formed into a movable
optical unit 610, which scans an original document in the
subscanning direction at a preset, fixed speed. A control section
612, formed from keys for setting and displaying various modes
regarding a copying sequence, liquid-crystal display devices, and
the like, is disposed in the periphery of the document holder 601.
Light reflected when the document radiation lamp 604 irradiates the
original document is caused to enter the CCD image sensor 608 via
the scanning mirrors 605 and 606 and the image-forming lens 607,
and various image processing operations are then performed by the
image processing apparatus. Reference numeral 611 denotes an image
leading-edge sensor. Reference numeral 613 denotes a DC (direct
current) servo motor for operating a scanner unit 609 and the
optical unit 610 (also referred to collectively as an "image
reading head") using a PLL (phase-locked loop).
[0048] FIG. 7 is a block diagram of the copying system according to
the second embodiment of the present invention. The copying system
comprises the image reading apparatus 614, which includes the CCD
image sensor 608, DC servo motor 613, and other components, as
described above. All of these components are controlled by a
controller within an image forming apparatus (also referred to as
an "image recording section") 615. The image forming apparatus 615
comprises a laser unit 617 for forming an electrostatic latent
image, a drum unit 618 for transferring a toner image from the
electrostatic latent image to paper, and a heat roller 619 as a
fixing means for fixing the transferred toner image to the paper.
The paper is fed from a paper-supply section 620, and is ejected to
a paper-ejection tray 621 after undergoing the above-described
process.
[0049] The power to the image reading apparatus 614 is supplied
from the main unit of the copying machine and is linked with the
power supplied to the overall copying machine. Furthermore, the
controller 616 collects information on the temperature around the
heat roller 619, making it possible to control the amount of
current provided to the DC servo motor 613, for reading an image,
and to the heat roller 619.
[0050] FIG. 9 is a block diagram showing the control construction
according to the second embodiment of the present invention. A
power unit 622 supplies power to the DC servo motor 613 and the
heat roller 619 via a motor control driver 623 and a heat roller
control driver 624. Furthermore, the motor control driver 623
receives a driving and current control signal from the controller
616, and is able to perform speed control of the DC servo motor
613. The temperature of the heat roller 619 is controlled by the
controller 616 via the heat roller control driver 624 in a similar
manner.
[0051] A circuit diagram showing the operation of the motor control
driver 623 is shown in FIG. 10. Both a driver 1 (625) and a driver
2 (626) obtain an operation permission signal from the driving
signal, and the selection of the drivers is made exclusively in
accordance with the power control signal. When a power control
signal ON is input to the driver 1 (625) in a state in which the
driving signal is ON, the DC servo motor 613 is operated at a first
backscan speed (normal speed). In the driver 2 (626), in contrast,
when the power control signal is turned off, the DC servo motor 613
is operated at a second backscan speed (decelerated speed). This
makes it possible to control the backscan speed of the DC servo
motor 613 according to the ON/OFF state of the power control signal
from the controller 616.
[0052] In the above-described control construction, processing is
performed in accordance with a control operation, as will now be
described, with reference to a control flowchart (see FIG. 11),
from a time when the power is switched on. When the power of this
copying system comprising both the image reading section and the
image recording section is switched on, or the system is being
restarted (step S627), initially, paper remaining within the
machine of the copying system due to a forced disconnection of the
power, during operation, or the like, is detected in step S628.
When such remaining paper is detected, processing for the paper
remaining within the machine is performed (step S629) to remove the
remaining paper.
[0053] After the above-described processing operation is
terminated, setting is performed in step S630 such that the
backscan speed of the DC servo motor 613 of the image reading
section is decreased by half, and temperature control is thereafter
performed in step S631. Then, heat detection (step S632) of the
heat roller 619 is performed, and control (steps S631) of the
amount of heat yielded by to the heat roller 619 is repeated, by
controlling the amount of current provided to the heat roller 619,
until the temperature of the heat roller 619 stabilizes to within a
specified temperature range within a reference time period.
[0054] When the temperature of the heat roller 619 is stabilized to
within the specified temperature range within the specified time
period (step S632), the value of electric current provided to the
heat roller 619, set previously in the initial operation (step
S630), is returned to a steady state operation value, and the
backscan speed is returned to the normal speed. As a result, the
control of the amount of current provided when the heat roller 619
is heated becomes a normal temperature adjustment operation (step
S633).
[0055] Timing charts showing various power consumptions, and
indicating advantages obtained by a control means such as that
described above, are shown in FIGS. 12a-12c A case is shown in
which a copying operation is started from when the power of the
copying system is switched on, or immediately after (point A) the
copying system is restarted. In the case of no backscan speed
control (634), at the backscan speed at point A, the same amount of
power as that during normal operation has already been consumed,
and if the amount of power consumption of the heat roller 619 is
added, the maximum value of the amount of power consumption is
greater than that during steady state operation. In the case of
backscan speed control (635), in contrast, the backscan speed
control makes it possible to reduce by half the maximum value of
the amount of power consumption.
[0056] As has been described up to this point, according to the
present invention, an image processing apparatus comprising an
image reading section and an image recording section includes a
means for decreasing the subscanning return speed of a portion of
the image reading section, including, for example, a facsimile
device, for a limited time period at a time when the power of the
image recording section is switched on, and lasting until a time
when the temperature adjustment of a heat roller for performing
fixing has terminated, and the amount of power consumption at that
time is distributed to the temperature adjustment of the heat
roller. This makes it possible to reduce the peak value of the
power consumption of the entire image processing apparatus.
Furthermore, by causing the image reading section to previously
operate during a warm-up time period in order to temporarily store
image information to be formed in a storage device, it is possible
to reduce the waiting time until the start of the overall
copying.
[0057] Many different embodiments of the present invention may be
constructed without departing from the spirit and scope of the
present invention. It should be understood that the present
invention is not limited to the specific embodiments described in
this specification. To the contrary, the present invention is
intended to cover various modifications and equivalent arrangements
included within the spirit and scope of the invention as hereafter
claimed. The scope of the following claims is to be accorded the
broadest interpretation so as to encompass all such modifications,
equivalent structures and functions.
* * * * *